NPPB and hydrops fetalis: The European Society of Cardiology currently recommends measuring NT-proBNP in the diagnosis of HF.14 Although NT-proBNP is recognized as the gold standard biomarker of AF and HF, it has some limitations.15 Moreover, as AF and HF are characterized by complex pathophysiological mechanisms,1,14 relying on single biomarkers may not adequately capture the complete disease process.